Tube-still regulation



. WU F. M. POOLE TUBE STILL REGULATION Filed July 28 1925 Jan. 25 1927.

W a/MZQ ATTORNEY Patented Jan. 25, 1927.

UNITED STATES,

FOSTER MAI-IO POOLE, OF TULSA, OKLAHOMA. ASSIGNOR T THE BROWN INSTRUMENT COMPANY, OF PHILADELPHIA, PENNSYLVANIA, A CORPORATION OF PENNSYL- VANIA.

TUBE-STILL REGULATION,

Application filed July 28, 1925. Serial No. 46,515.

The general object of the present'invention is to provide an improved method of, and improved means for regulating the operation of tube oil stills; and the invention is characterized by the fact that the supply of heat to the still is made dependent on the temperature of the oil passing through the still at a point in its path of travel at which the oil is somewhat/below the maximum or still exit oil temperature.

By making the operation of the furnace dependent on the oil temperature at an intermediate point in the path of oil travel through the still instead of on the temperature at which the oil leaves the still, as

has been done heretofore, certain important practical advantages are obtained. For one thing variations in conditions of operation requiring compensating changes in the rate 0 of heat supplycreate significant changes in oil temperature more quickly at a point in the path of oil travel at which the oil temperature is appreciably below that of the exit temperature of the oil. than at the oil exit. Any decrease in the time interval between a change in oil temperature and the posits insulating the thermocouple or other thermo-sensitive control device from the temperature to which it is intended to re spond.

The various features of novelty which characterize my invention are pointed out with part cularity in the claims annexed to and forming a part of this specification; but for a better understanding of the invention, its'advantages, and Specific objects at-- tained with its use reference should be had to the accompanying drawings and descriptive matter in which I have illustrated and described a preferred embodiment of my invention.

Of the drawings:

Fig. 1 is a diagrammatic representation of an oil still; and

it eliminates or minimizesdifiiculties of control caused by carbon de- Fig. 2 is an enlarged view of a. portion of the apparatus shown in Fig. 1.

In Fig. 1, I have diagrammatically illustrateda conventional form of oil tube still comprising a furnace housing A, the upper portion of the interior of which is traversed by a bank of horizontally disposed tubes B, which are located above a combustion chamber A, and between the latter and a stack outlet A for the escape of the spent heating gases. The tubes Bare shown as connected by external return bends B and B to cause the o1l to flow in series through tubes A at success vely lower levels from anupper oil inlet pipe C'to a lower oil outlet pipe D. The stillisheated by the combustion of oil or gas supplied under suitable pressure through I a burner pipe E at a rate dependent on the adpistment of a control valve E As shown, air for combustion is drawn by the. I

stack suction into the combustion chamber A from the external atmosphere through the opening A in the furnace housing through which theburner pipe E projects into the combustion chamber. It will be,

understood that the apparatus-as above described embodies no part of the present invention, but on the contrary constitutes merely one typical-form of tubular oil still with which the invention may be employed with advantage.

In accordance with the present invention, the regulating valve E is opened and closed in automatic response to the temperature of.

the oil at a point in its path of travel through-the still intermed ate the inlet 0 and the outlet D, and preferably 'in most the oil ,exit than the oil entrance temperature. To this end, inthe particular form of apparatus illustrated by way of example, the return bend B is formed with a-well or tubular casing B extending-into its oil passage to receive a the-rmo-scnsitive device F, whichordinarily is a thermocouple, The terminals of the device Fare connected to a suitable control instrument G. 'The latter may be an indicating or recording galvacases Where the oil temperature is nearer nometer with control provisions of known form as shown, for example, in the patent 1 to Brown No. 1,355,448, granted October 12,

1920, for a reversible relay motor operated valve actuating mechanism H for adjusting the valve E The-mechanism may be of i the known l and 2 in the direction required to\give an opening movement to the valve E and thereby increase the fuel supplied to the combustion chamber A, when a temperature reduction in the return bend. B causes the instrument G to connect the motor terminal 3 to .the supply conductor 2. Conversely when the tem erature in tlie return bend B increases a ove normal the instrument G connects the motor terminal 4 to the supply conductor 2 and the valve E is then adjusted to reduce the rate of fuel supply to the chamberA'.

I is a 'thermo-couple or other thermometric device provided as is usualfor measuring the still oil exit temperature. As shown, the device I is inserted in a thermometer well J between the stilloil outlet proper, and the still delivery pipe 0.

\Vith the wellvB containing the control thermo-couple F located at a point at which the oil temperature is below the still exit temperature, carbon deposits on the outer wall of the well B? may or may not occur depending on the conditions of operation, but if carbon does deposit on the wall B such deposit will in practice alwa s be less than the simultaneously formed eposit on the outer wall of the well J. Carbon deosits on the walls of the therometer wells E and J tend, of course, to make the thermometric devices in said wells indicate lower temperatures than the actual temperatures of the oil in contact with the respective wells. In consequence the errors, if any, in

the indications of the instrument G due to carbon deposits will be less with the instru ment G responsive to the temperature in the well B than if responsive to the temperature in the well J. The existence of errors. 'in the lndicatlons of an instrument connected to a thermo-couple 11 due to carbon deposits on the well J can be detected and their extent approximated by an ordinary approximately by the amount of difl'erence shown by the patent to such errors by means of the adjusting provisions with which the control instruments like the instrument G are automatically provided. As a net result the location of the thermocouple to which the control instrument G is responsive to the well B instead of in the well J, permits longer runs or periods 5 of still operation between the inevitably necessary shut-downs for carbon removal.

Having now"desc1'ibed my invention wh'at I claim as new and desire to secure by Letters Patent is:

1. In operating an oil heater of the type comprising tubes connected to form an elongated path of oil travel and means for heating said tubes and thereby progressively heating oil traveling along said path, the method which consists in varying the oil heating effect in inverse response to changes in the temperature of the oil at a point in the path of oil travel through thestill intermediate the entrance and exit ends of said path. I

2. Ir operating an oil comprising tubes connected to form an elongated path of oil travel and means for heating said tubes and thereby progressively heating oil traveling along said path, the method which consists in varying the oil heating effect in inverse response to changes in the temperature of the oil at a point in the path of oil travel through the still at.

which the oil temperature is somewhat below the maximum oil temperature attained in the still.

3. Anoil heater com" using tubes connected to form an elongz ted path of oil travel between a heater O11 inlet and a heater oil exit. of combustion regulating provisions therefor including a thermo-sensitive de-- vice responsive to the temperature of the oil'passing along said path at a point thereof at which the oil temperature is intermediate the oil entrance and exit temperatures, and means actuated by said device for increasing and decreasing the still heat supply as the temperature to which said device responds decreases and increases.

Signed at St. Louis. in the county of St.

heater of i the type,

Louis, and State of lilissourh this 21st day of July, A. DJ 1925.

- FOSTER MALIC POOLE. 

